The comic will present a teatime talk show half the year, while Richard and Judy will continue to present their 5pm chatshow the rest of the year.

Kevin Lygo, of Channel 4, said the network would be "packing an incredibly powerful punch" in the afternoon.

O'Grady, famed for his alter ego Lily Savage, signed for his daily ITV chat show in 2004 and went on to beat rivals Richard and Judy in the ratings.

He was handed the slot after impressing ITV bosses with guest stints on This Morning and Today with Des and Mel.

I work best when I'm set a new challenge and am forced to fly by the seat of my pants

Paul O'Grady

The 50-year-old entertainer, who recovered from a heart attack nearly four years ago, has signed a two-year deal with Channel 4.

"It's lovely to share the line-up with Richard and Judy and make Channel 4 the only place to be at teatime," he said.

"My time at ITV with The Paul O'Grady Show surpassed all my expectations and I'm indebted to everybody who worked on it and watched it, but I work best when I'm set a new challenge and am forced to fly by the seat of my pants.

"A move to Channel 4 does exactly that and I look forward to a fresh start and feeling sick with nerves again."

O'Grady's new contract is not exclusive but it prevents him from continuing to present his ITV1 daytime show. His new show is expected to start in the spring.

An ITV spokeswoman said they were proud of the show's success.

"We have enjoyed a very successful year with the Paul O'Grady Show, winning every daytime award going as well as great ratings and we are glad that it has ended on a high," she said.

'Fierce battleground'

Richard Madeley and Judy Finnigan have agreed to extend their contract for another year.

Channel 4's director of television Kevin Lygo said: "Daytime is currently one of the fiercest battlegrounds and so to have three of the biggest names in daytime TV joining forces on Channel 4 is a fantastic coup for us.

"Paul is one of the warmest and wittiest presences on television and we're absolutely thrilled to welcome him back to Channel 4.

"Richard and Judy have been tremendous performers for us at teatime, both in terms of ratings and reputation, and we're delighted that they've committed to us for at least another year."

Richard Madeley described O'Grady's move as "terrific news".

"We are old mates of Paul's and used to work really well together on This Morning. It's great that we are not having to trade punches with each other any more now he's joining the Channel 4 team," he said.